Near the Okutsumiya portion of Enoshima Shrine are two strange stones presented as offerings in olden times, known as kame-ishi (turtle rock) and chikara-ishi (strength rock).

This one, visibly patterned like a turtle’s shell, is kame-ishi, also known as zōroku-ishi (based on another word for “turtle”).
This place used to be called Kinkizan Yoganji temple, and because that name contained the character for “turtle” (亀), the rock was dedicated as an offering here.
The shrine at Okutsunomiya has turtle motifs hidden everywhere, including on the ceiling and at the ritual cleansing station. Try to spot them all!

This is called chikara-ishi (strength rock). Unosuke that was said to be Japan's powerful person in the Edo era dedicated to the shrine .
The weight is 320kg and this was used for lifting race during festivals.
The signboard says "Please do not lift", but who would lift 320kg stone?